The present invention relates to an apparatus for testing various properties of envelopes.
The envelope manufacturing industry involves the production of an extremely large number of units at a very high-speed production rate and a minimal material cost per unit. During envelope production, several key criteria, such as the consistency of the application of adhesive along the front seal and the strength of the bond along the side and back seams, are critical to the manufacture of an acceptable envelope. The industry is continuously striving to maximize the output of units and minimize return and waste units, many of which are caused by failures in the above key criteria. The industry""s profits and sales are based upon the minimization of failures in the envelopes.
A number of obstacles have arisen in recent years which have resulted in decreased sales and profits for the industry. One cause is the increase in alternative means of communication, such as the Internet, that do not require the use of envelopes. Further, the tragic events of Sep. 11, 2001 and subsequent anthrax scare have placed an increased focus on safety and security within the industry. A separate issue has been created by the increased use of recycled paper in that such recycled paper does not always bond as neatly as non-recycled paper.
Accordingly, the envelope manufacturing industry is in need of a system for inspecting envelopes in order to ensure that envelopes are structurally sound before they are shipped to customers. It would be advantageous if such a system could inspect key features of the envelope, such as the consistency of the adhesive along the front seal and the strength of the bond along the side and back seams. Such a system would provide distinct competitive and economic advantages to an envelope manufacturer.
The present invention discloses a unit for evaluating various properties of a paper envelope. The unit is capable of examining an envelope and determining key features of the envelope, such as the amount of front seal adhesive present, the tear strength of the side seams and the presence of properly printed graphics. The unit comprises a) a housing having either a touch screen video display unit or another source df data entry; b) a front seal control portion that contains linear encoders to determine the amount of adhesive on the seal; c) a side strength control portion that contains blades used to measure the force needed to burst the sides of the envelope; and d) a print design quality feature that is utilized to confirm the quality and location of any printing on the envelope.